The present invention relates to, for example, the technical field of a seatbelt device attached to a seat of a vehicle, such as an automobile. More particularly, the present invention relates to a seatbelt device which can constrain an occupant by placing a seatbelt under tension by operating a pre-tensioner at the time of an emergency, such as a collision of the vehicle.
Conventionally, a seatbelt device is attached to a seat of a vehicle, such as an automobile. When a very large deceleration of a vehicle occurs at the time of an emergency, such as a collision of the vehicle, a seatbelt constrains an occupant and restricts the inertial movement of the occupant in order to protect the occupant. Certain seatbelt devices include a pre-tensioner which constrains an occupant quickly and with a large constraining force by placing the seatbelt under tension at the time of the aforementioned emergency. In general, the pre-tensioner is provided at a seatbelt retractor of the seatbelt device, but may also be provided at a buckle or a lap anchor section.
The retractor is typically one of several types including, for example, an emergency seatbelt retractor (ELR), an ELR including a pre-tensioner, and an ELR including a load limiter that absorbs impact energy by limiting the load exerted on the seatbelt during an emergency.
In an emergency, when the pre-tensioner operates to pulls the seatbelt substantial force is applied to seatbelt. As a result, a large shock is applied to the components of the seatbelt device including, for example, the buckle. Therefore, there is a need for a seatbelt device that provides for increased shock absorption upon operation of the pretensioner.